Higher-level (mental, sociological and biological, etc.) entities are said to be supervenient on more basic, lower-level (physical, micro-level) entities, and there is a view that lower-level theories can completely and sufficiently explain higher-level events. But Harold Kincaid criticizes such a view. He does not deny that lower-level theories do explain something, but argues that they are only partial and incomplete, because they cannot refer to higher-level kinds which supervene on the relevant lower-level entities and answer important questions about causal laws. I will argue that the completeness or sufficiency of explanation is often evaluated interest-relatively, and, against Kincaid, that higher-level explanation cannot be sufficient without mentioning lower-level causal mechanism.